Wise move. The only way I managed to kill it was with Ortho's Poison Ivy and Tough Brush Killer* (undiluted) but that came only after many years of digging to no avail. They grow from the tiniest piece accidentally left in the earth.
*Do not spray with any tank sprayer or you can kill desirable plants. You could put some killer in a sandwich sized plastic bag and bend the stem into the bag so the killer won't bother any other plants but if it's too close to anything good, be sure to protect the good plants very well (boxes, plastic bags, etc.) or you'll regret it.
